In gas turbine engines, compressed air discharged from a compressor section and fuel introduced from a source of fuel are mixed together and burned in a combustion section, creating combustion products defining a high temperature working gas. The working gas is directed through a hot gas path in a turbine section, where the working gas expands to provide rotation of a turbine rotor. The turbine rotor may be linked to an electric generator, wherein the rotation of the turbine rotor can be used to produce electricity in the generator.
In view of high pressure ratios and high engine firing temperatures implemented in modern engines, certain components, such as airfoil assemblies, e.g., stationary vane assemblies and rotating blade assemblies within the turbine section, must be cooled with cooling fluid, such as compressor discharge air, to prevent overheating of the components and to reduce thermal stress in the components.